Method of and apparatus for refrigerating materials



L. N. UDELL July 31, 1934.

METHOD OF AND APPARATUS FO R REFRIGERATING MATERIALS Filed July 29. 1951 4 Sheets-Sheet l I lmjanlfir I 021/05 JV U dlcl L. N. UDELL July 31, 1934.

METHOD OF AND APPARATUS FOR REFRIGERATING MATERIALS Filed July. 29, 1931 4 Sheets-Sheet 2 lmvem fyk louzls JV Ud/ebb,

L. N. UDELL 1,968,543 METHOD OF AND APPARATUS FOR REFRIGERATING MATERIALS July 31, 1934.

Fil ed July 29, 1951 4 Sheets-Sheet 3 L. N. UDELL July 31, 1934.

METHOD OF AND APPARATUS FOR REFRIGERATING MATERIALS Filed July 29, 1931 4 Sheets-Sheet 4 Patented July 31, 1934 UNITED STATES METHOD OF AND APPARATUS FOR REFRIGERATING MATERIALS Louis N. Udell, Boston, Mass.

7 Application July 29, 1931, Serial No. 553,716

23 Claims.

This invention relates to a new and improved method of and equipment for effecting refrigeration of materials, and more especially food products such as fish, meats, etc. Several specifically different methods of refrigerating such products heretofore used have involved broadly the packing of the goods in a pan-shaped container or receptacle of heat conducting material, such as metal, applying thereto a cover, and then subjecting the receptacle and its cover to direct contact with a body of liquid refrigerantfor a sufiicient length of time to thoroughly chill or freeze the contents. In one known method, the containers are floated along a flowing stream of brine or other liquid refrigerant for a sufficient length of time to effect the refrigeration. A modification of the last-named method consists in showering upwardly convex covers of the containers with liquid refrigerant as they are floated through the refrigerating channel. Another method is known in the trade as the diving bell method and consists in stacking a group of covered containers in a frame, and then lowering the loaded frame into a body of liquid refrigerant, the air seal formed between the body and the overhang ing cover flange of each container being relied upon to prevent the refrigerating liquidfrom gaining access to the material in the containers. Still another known method consists in placing the receptacles or containers within a sealed cham ber that is sub-divided by horizontal partitions or shelves supporting the receptacles, locking the receptacles in place, and then flowing a stream of liquid refrigerant successively through the several compartments from top to bottom, the receptacles being bathed by the flowing stream of refrigerant.

All of the above described niethods are fairly successful in operation, but nevertheless possess some faults and defects. The flotation system, for instance, requires a channel or runway of a lengththat renders the apparatus undesirably bulky and necessitates the use of an objectionably large area of floor space, and the time required for complete freezing is undesirably protracted. In the diving bell system, considerable care has to be exercised to prevent danger of a failure of the air seal and the penetration of the goods by the refrigerating medium, which spoils the goods. The sealed chamber system involves considerable time and labor in sealing and unsealing the chamber when the same is to be loaded and unloaded. This system is also subject to the danger of penetration of the goods by the refrigerant, since the receptacles are completely submerged, as in the diving bell system.

It is the general object of the present invention to provide a system of refrigeration which will successfully obviate the above noted defects of previous systems, will shorten the time required for eflicient refrigeration, and will be comparatively inexpensive to manufacture and easy to operate. Other and more specific ob jects of the invention will be apparent as the same becomes better understood by reference to the following detailed description, taken in connection with the accompanying drawings, wherein I have illustrated two practical and approved embodiments of the principle of the invention, and in which:

Fig. l is a side elevation, broken out and partly in vertical section, of an apparatus designed to effect what I term the cascade method of re frigeration.

Fig. 2 is a horizontal section taken on the line 2-2 of Fig. l.

Fig. 3 is an isometric view of one of the refrigerating units shown in Fig. l detached from its supporting frame. 7

Fig. 4 is an enlarged vertical transverse section through one side of the refrigerating unit, taken on the line 4=4 of Fig. 3.

Fig. 5 is a vertical oblique section through one corner of the unit, for example on the line 5-5 of Fig. 3. V

Fig. 6 is a fragmentary outside elevation of one corner of the unit.

Fig. 7 is a side elevation, broken out between its ends and partly in vertical section, of an apparatus embodying the unit principle and construction of Figs. 1 to 6 inclusive, and designed and adapted to effect continuous operation, with loading, freezing and unloading operations going on simultaneously.

Fig. 8 is a top plan view of Fig. 7.

Fig. 9 is an end elevation, with one unit in vertical transverse section, of the apparatus shown in Figs. '7 and 8.

Fig. 10 is an isometric fragmentary view of one of the units shown in Figs. 7, 8 and 9.

Referring first to the form of the invention illustrated in Figs. 1 to 6 inclusive which, as above stated, in the multiple unit form shown in Fig. 1, embodies What I term the cascade principle, 1 designates each of four upright supports herein shown as angle bars that are spaced and connected by a series of tanks 2 secured thereto as by rivets welding, etc., at point 3. As all of the units, each of which includes a tank 2, are identical, description of one will sufiice for all.

Disposed within the tank 2 is a pan 4 constituting a receptacle or container for the goods, such as fish, meat or the like to be refrigerated. This pan 4 is so supported that its bottom wall will be spaced from the bottom wall of the tank 2, and for this purpose I have shown the bottom wall of the tank as provided with a series of spacing bars 5 on which the pan rests. The tank 2 is preferably .formed with a central hollow boss 6 of such a height that when the pan 4 is seated in the tank a restricted annular outflow opening 7 will be provided between the bottom of the pan 4 and the upper edge of the boss 6. The tank 2 is further equipped, preferably in one corner thereof, with a short pipe or hollow boss 8, that affords an overflow duct from the tank determining the maximum level of the refrigerant therein. The lower end of this overflow duct is so located that it will overhang the dished cover of the next underlying unit. The spacing bars 5 and outlet boss 6 may be omitted in the bottom wall of the tank, and the pans may be allowed to float in the body of brine without any other supports, thus permitting circulation of brine under the bottom of the pan. This may, however, result in the tipping or tilting of the pan, and a support or supports to hold the pan above the bottom of the tank are preferred.

Cooperating with the pan 4 is a cover preferably of dished form comprising, in the instance shown, a flat bottom wall 9, side walls 10, and end walls 11, which have a height somewhat exceeding that of the side walls 10. As best shown in Fig. 4, the side walls 10 are extended horizontally at their upper edges as shown at 12 and thence downwardly in the form of depending flanges oraprons l3 overhanging the corresponding side walls of the pan 4. This construction forms on the opposite sides of the dished cover overflow weirs for a body of brine in the dished cover, said weirs directing the overflow from the coverv downwardly into the tank 2, and the flanges or aprons being preferably sufliciently long. to dip into the body of brine in the tank 2, when the cover has been applied to a loaded pan, as shown in Fig. 4.

Above the topmost unit of the series is a pipe 14 through which the liquid refrigerant, such as calcium chloride or sodium chloride, previously cooled to a sub-freezing temperature, is delivered directly into the dish-shaped cover of the top: most refrigerating unit. This cover having been filled, the refrigerant overflows through the weirs on the sides of the cover down into the tank 2, filling the latter up to the level of .the overflow duct 8. The refrigerant flowing through opening '7 and boss 6 and overflowing through the duct 3 falls into the dish-shaped pan of the next underlying unit, and so on through the vertical series, the discharge from the lowermost tank being conducted to the brine-cooling means (not shown) and then recirculated in the manner described.

From the foregoing it will be seen that the refrigerating medium comes into intimate contact with both the bottom wall of the pan 4 and the bottom wall 9 of the dished portion of the cover, both of which walls are normally in contact with the material being chilled or frozen, so that transfer of heat takes place from both the bottom and top of the material. It will also be noted that the upper end of the overflow 8 of the tank is lower than the upper edge of the pan 4, so that the refrigerant can never rise to a point at which it will enter the panand spoil the goods in the latter.

When the goods have been chilled or frozen, the pans and their covers can readily be withdrawn laterally from the tanks and the support ing frame, and the several tanks 2 are spaced sufficiently far apart to permit this. And since it is somewhat awkward to remove the pan and its cover when the latter is filled with the refrigerating liquid, I preferably provide at one or more corners of the pan a drain or drains 15 that are substantially at the level of the bottom wall of the dished cover, as shown in Fig. 5, so that, after the main flow of the refrigerant through pipe 14 has been cut off, the bodies of liquid, in the several covers will drain off, and the pans and covers can then be removed and handled without waste or slopping of the refrigerating liquid. Since the drain spouts 15 are partly below the top of the pan 4, as shown in Fig. 5, I notch out the corner portions of the side and end walls of the pan, as shown at 16 to accommodate the drain spouts 15.

In the normal operation of the system, the principal outflow from each upper tank into the dished cover of the next underlying pan is through the annular opening 7 in the bottom of the tank. In the event that the rate or" inflow should, however, exceed discharge capacity of the opening 7, the overflow duct 8, at a higher level, takes care of the same and limits the height to which the liquid canrise in the tank, the discharge from such overflowduct also being directed into the next underlying cover.

The equipment may be, and preferably is, rendered portable by equipping the corner posts 1 with suitable castors, such as the balls 18, or otherwise. This is a pronounced convenience, since it enables the apparatus to be readily shifted between a fixed refrigerant supply pipe 14 and more or less distant points for loading and unloading the product.

In Figs. 7 to 10 inclusive, I have illustrated an equipment that embodies the unit construction of the equipment previously described, and adapts the same to continuous operation, by which I mean the simultaneous receiving, freezing and discharging of receptacles containing the material being treated. In this embodiment of the 1nvention, instead of using tanks such as the tanks 2, of a size adequate to receive but a single pan.

I employ long tanks or troughs 20 that are arranged in 2. tier of any desired or practical height and may be supported and spaced at their longitudinal edges by interposed supports such as blocks 21, best seen in Fig. 9. In each trough 20 is disposed aline of pans 22 to hold the fish or other articles to be frozen. These pans are so formed and supported as to be readily slidable either by a push or a pull, through and lengthwise of the trough. I have herein shown each pan as formed with horizontal flanges 23 on its 7 ends that rest on rollers or wheels 24 journaled in the side walls of the trough 20, but any other convenient means for slidably supporting the pansto move through the trough may, of course, be employed.

Or, if the goods to be cooled are not too heavy, it is possible to make the loaded pans buoyant in the liquid refrigerant contained in the trough. in which case the rollers or wheels 24 may be omitted, as the buoyant panscan be very readily pulled or pushed through the trough.

The dished covers 250i the pans may be, and. are herein shown as, identical structurally with the dished covers of the pans previously described in connection with Figs. 1 to 6 inclusive.

Extending lengthwise of and above each trough, at a suitable height to conveniently serve the dished covers of the pans mounted in the trough, is a refrigerant supply pipe 26 equipped at intervals corresponding to the spacing of the pans with depending delivery nozzles 27, this pipe being, of course, capped at one end as shown at 28 and at its other end connected with a source of refrigerant supply.

To facilitate movement of the line of pans along the trough by either a manual push or pull, the pans may be connected by simple coupling links 29, or, in lieu of this, the pans may be power-moved through the agency of a simple conveyor mechanism.

In this embodiment of the invention, since each unit of the tier may, and preferably will, include a troughand line of receptacles sufficiently long to effect freezing during theprogress of each receptacle from the entering end to the discharge and of the trough, I do not supply the refrigerant on the cascade principle shown in Fig.1, (although this may be done if desired) but I preferably supply refrigerant independently to each unit, as shown. This may be supplied through ppe 26 and nozzles 27 to the dished covers only, and by overflow from the latter to the trough, but I preferably also supply the refrigerant to the trough as by a supply pipe connected into one end of the trough as at 30 and one or more discharge pipes connected into the other end of the trough as at 31 at a level above the bottom wall of the trough and preferably slightly below the level of the upper edge of the trough, so as to maintain in the trough a body of suflicient depth to bathe the bottom wall and in part the side walls of the pans. Here too, however, the overflow or discharge from the trough is held at a point below the upper edges of the pans, so that, regardless of any air seal, the refrigerating liquid can never obtain access to the contents of the pans.

In this system I have found it practical to omit the overhead supply of refrigerant through the pipe 26 and supply refrigerant only to the trough,

where the covers of the pans are made of goodv heat conducting material, and are formed with depending flanges or aprons dipping down into the body of refrigerant in the trough. In this Way, the heat in the upper portion of the product being chilledis readily conducted through the cover into the body of refrigerant which underlies and surrounds the pan itself.

In Fig. '7 I have shown the end portions of the troughs 20 as extending some distance beyond the ends of the series of spacingsupports 21, and I have also shown the bottom wall of the trough upwardly inclined at 20'. These structural features facilitate the placing of the loaded receptacles into, and their removal from, the ends of the troughs.

It will be obvious to those skilled in the art that various changesmay be made in the devices herein shown and described without departing from the spirit of the, invention orsacrificing any of the benefits and advantages thereof; and

accordingly I do not limit myself, to the specific structures shown and described for purposes of illustration, but reserve all such variations; modfications and mechanical equivalents as fall within the spirit and purview of theiappended claims.

. I claim:

1. A method of refrigeration, which cons sts in packing the goods to be refrigerated in a pan having a dished cover, pouring a liquid refrigerant into said cover and permitting the refrigerant to overflow therefrom at a fixed level whereby to maintain in said cover a body of refrigerant of constant depth, and simultaneously subjecting the side and bottom walls of said pan to contact with a body of liquid refrigerant including overflow from said cover.

2. A method of refrigeration, which consists in packing the goods to be refrigerated in a pan having a dished cover, pouring a liquid refrigerant into said cover and permitting the refrigerant to overflow therefrom at a fixed level whereby to maintain in said cover a body of refrigerant of constant depth, simultaneously subjecting the side and bottom walls of said pan to contact with a body of liquid refrigerant, and limiting the depth of said last-named body to a point at which it cannot overflow into said pan.

{Refrigerating apparatus of the type de scribed, comprising an open top tank, a pan to contain the goods to be refrigerated disposed in said tank, a dished cover for said pan, means for supplying a liquid refrigerant to said cover, means for directing the overflow from said cover to said tank, and means for so discharging the liquid from said tank as to maintain a body of liquid in said tank around said pan.

4. Refrigerating apparatus of the type described, comprising an open top tank, a pan to contain the goods to be refrigerated disposed in said tank, a dished cover for said pan formed with an overflow weir overhanging a side wall of said pan to direct the overflow from said cover into said'tank, means for supplying a liquid refrigerant to said cover, and means for so discharging the liquid from said tank as to main tain a body of liquid in said tank around said pan.

5. Refrigerating apparatus of the type described, comprising an open top tank, a pan to contain the goods to be refrigerated disposed in said tank with the bottom wall of said pan spaced from the bottom wall of said tank, a dished cover for said pan formed with an overflow Weir overhanging a side wall of said pan to direct the overflow from said cover into said tank, means for supplying a liquid refrigerant tosaid cover, and means for so discharging the liquid from said tank as to maintain a body of liquid in said tank beneath and around said pan.

6. Refrigerating apparatus of the type de scribed, comprising an open top tank, a pan to contain the goods to be refrigerated disposed in said tank with the bottom wall of said pan spaced from the bottom wall of said tank, a dished cover for said pan formed with an overflow weir overhanging a side wall of said pan to direct the overflow from said cover into said tank, an overhead pipe fo-rdelivering a liquid refrigerant into said cover, and an overflow duct in said tank lo cated at a level such as to maintain a body of liquid in said tank beneath and around said pan.

7. A cascade method of refrigeration, which consists in arranging a plurality of covered re- Med said cover into tlietopmosttank and: around and beneath the body of the topmost receptacle, and similarly conducting the down flow of refrigerant successively onto and through the underlying units of the tier. i

9. Multiple unit refrigerating apparatus of the type herein described, comprising an upright skeleton frame, and a plurality of refrigerating units mounted in vertically spaced relation in said frame; each of said units comprising anopen top tank, a pan to contain the goods to be .refrigerated disposed in and removable from. said tank,.a cover for. said pan, and means for-directing drainage from said cover into said tank; means for supplying a liquid refrigerant to the cover of the topmost unit, and means for directing overflow from each tank, except the lowermost, onto the cover of the next underlying unit, said last-namedmeans serving to maintain a body of liquid in each tank around the pan dis-, posed therein.

10. Multiple unit refrigerating apparatus of the type herein described, comprising an upright skeleton frame, and a plurality of refrigerating units mounted in vertically spaced relation in said frame; each of said units comprising an open top tank secured within said frame, a pan to con tain the goods to be refrigerated disposed in and removable from said tank, and a dished cover for said pan formed with an overflow weir overhanging a side wall of said pan to direct overflow from said cover into said tank, an overhead pipe for delivering a liquid refrigerant. into the cover of the topmost unit, and meansfor discharging the liquid from each tank, except the lowermost, into the cover of the next underlying unit, said last-named means serving to maintain a body of liquid in each tank around the pan disposed therein.

11. Multiple unit refrigerating apparatus of the type herein described, comprising an upright skeleton frame, and a plurality of refrigerating units mounted in vertically spaced relation in said frame; each of said units comprising an open top tank secured within said frame, a pan .to contain the goods to be refrigerated disposed in and removable from said tank, and a dished cover for said pan formed with an overflow weir overhanging a side wall of said pan to direct overflow from said cover into said tank, an overhead pipe for delivering a liquid refrigerant into the cover of the topmost'unit, and means for discharging the liquid from each tank, except the lowermost, into the cover of the next underlying unit. said last-named means comprising a re stricted outflow passage in the bottom wall of the and an overflow duct at a higher level than said restricted passage; saidunits being spaced sufficiently to permit lateral insertion and withdrawal of said pans and their covers through the sides of said frame.

12. In a refrigerating apparatus of the type described, a container for the goods to be refrigerated, comprising a pan, and a dish-shaped cover therefor, said cover formed with an overflow weir in a side wall of the dished portion thereof,

13. In a refrigerating apparatus of the type described, a container for the goods to be refrigerated, comprising a pan, and a dish-shaped cover therefor, said cover formed with a lateral drain substantially at the level of the bottom wall of its dished portion.-

14. In a refrigerating apparatus of the "type described, a container for the goods to be refrigerated, comprising a pan, and a dish-shaped cover therefor, said cover formed with a lateral drain substantially at the level of the bottom wall of its dished portion, and with an overflow'weir in a side wall of said dished portion. -15. Refrigerating apparatus of the type described, comprising an open top trough, means for'supplying a liquid refrigerant to said trough, means for discharging the refrigerant from said trough so as to carry a body of refrigerant in the trough, and a line of pans to contain the goodsto be refrigerated dipping into the body of refrigerant in said trough, said pans formed with flanges slidably supported on the side walls of said trough whereby the line of pans may be moved bodily lengthwise of said trough.

16. Refrigerating apparatus of the type described, comprising an open top trough, a line of pans to contain the goods to be refrigerated supported on the side walls and slidable lengthwise of said trough, covers for said pans, means for pouring a liquid refrigerant onto said covers, means for directing drainage from said covers into said trough, and means for discharging the refrigerant from said trough so as to carry a body. of refrigerant in the trough; said pans dipping into the body of refrigerant in said trough.

17. Refrigerating apparatus of the type described, comprising an open top trough, means for supplying a liquid refrigerant to said trough, meansfor discharging the refrigerant from said trough soas to'carry a body of refrigerant in the trough, a line of pans to contain the goods to be refrigerated supported on the walls and slidable lengthwise of said trough and dipping into the body of refrigerant therein, covers for said pans, means for pouring a liquid refrigerant ontosaid covers, andmeans for directing drainage from said covers into said trough.

18. Refrigerating apparatus of the type described, comprising an open top trough, means for supplying a liquid refrigerant to said trough, meansfor discharging the refrigerant from said troughso as to carry a body of refrigerant in the trough, a line of pans to contain the goods to be refrigerated supported by and slidable lengthwise of said trough and dipping into the body of refrigerant therein, dished covers for said pans, means-for delivering a liquid refrigerantinto said covers, and means for directing overflow from said covers into said trough.

19. Multiple unit refrigerating apparatus of the type herein described, comprising a plurality of units as defined in claim 15 arranged in a vertical tier, and supporting and spacing blocks between the side walls of the troughs of superposed units, said troughs at their ends extending beyond said supporting and spacing blocks, whereby to facilitate insertion and withdrawal of loaded pans into and from the ends of their respective troughs.

20. Refrigerating apparatus of the type described comprising an open top trough, means for supplying a liquid refrigerant to said trough, means for discharging the refrigerant from said trough so as to carry a body of refrigerant in the trough, a line of pans to contain goods to be refrigerated movable buoyantly lengthwise of said trough, dished covers for said; pans, means for supplying liquid refrigerant to said dished covers, and means for discharging said refrigerant from said covers to said trough so as to maintain a body of refrigerant in said dished covers, substantially as set forth.

21. The method of quick-freezing which con- 3 23. Quick freezing apparatus comprising means for holding a bath of refrigerant, a closed container having means exterior thereof and at the top to retain a body of refrigerant, means engaging the container extending in partially submerged condition in said bath for moving said container in the bath, and means for discharging refrigerant upon the top of said container.

LOUIS N. UDELL. 

